:root {
    --bg: #ffffff;
    --surface: #f6f7f9;
    --border: #e3e6ea;
    --text: #15181d;
    --muted: #5b626d;
    --accent: #1f6f5c;
    --accent-soft: #e8f3ef;
  }
  @media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) {
      --bg: #101316;
      --surface: #171b20;
      --border: #272c33;
      --text: #eef1f4;
      --muted: #a2aab5;
      --accent: #5fc0a4;
      --accent-soft: #15231f;
    }
  }
  :root[data-theme="dark"] {
    --bg: #101316;
    --surface: #171b20;
    --border: #272c33;
    --text: #eef1f4;
    --muted: #a2aab5;
    --accent: #5fc0a4;
    --accent-soft: #15231f;
  }
  * { box-sizing: border-box; }
  body {
    margin: 0;
    background: var(--bg);
    color: var(--text);
    font: 16px/1.65 system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    -webkit-font-smoothing: antialiased;
  }
  .wrap { max-width: 760px; margin: 0 auto; padding: 0 16px; }
  header { border-bottom: 1px solid var(--border); }
  .bar {
    display: flex; align-items: center; justify-content: space-between;
    gap: 16px; padding: 20px 0;
  }
  .logo { font-size: 1.15rem; font-weight: 700; letter-spacing: -0.015em; }
  .logo span { color: var(--accent); }
  nav a {
    color: var(--muted); text-decoration: none; font-size: 0.92rem; margin-left: 18px;
  }
  nav a:hover { color: var(--text); }
  h1 {
    font-size: clamp(1.75rem, 5vw, 2.5rem);
    line-height: 1.2; letter-spacing: -0.025em; margin: 48px 0 16px;
  }
  .lead { font-size: 1.08rem; color: var(--muted); margin: 0 0 36px; }
  h2 {
    font-size: 1.15rem; letter-spacing: -0.01em;
    margin: 44px 0 14px; padding-top: 28px; border-top: 1px solid var(--border);
  }
  ul { padding-left: 20px; margin: 0 0 20px; }
  li { margin-bottom: 8px; }
  .cards { display: grid; gap: 12px; grid-template-columns: 1fr; margin: 0 0 8px; }
  @media (min-width: 620px) { .cards { grid-template-columns: repeat(3, 1fr); } }
  .card {
    background: var(--surface); border: 1px solid var(--border);
    border-radius: 10px; padding: 16px;
  }
  .card h3 { margin: 0 0 6px; font-size: 0.95rem; }
  .card p { margin: 0; font-size: 0.9rem; color: var(--muted); }
  .box {
    background: var(--accent-soft); border: 1px solid var(--border);
    border-radius: 10px; padding: 16px 18px; margin: 24px 0;
  }
  .box p { margin: 0; font-size: 0.93rem; }
  dl { margin: 0; }
  dt { font-size: 0.78rem; text-transform: uppercase; letter-spacing: 0.05em; color: var(--muted); margin-top: 14px; }
  dd { margin: 2px 0 0; font-variant-numeric: tabular-nums; }
  a { color: var(--accent); }
  footer {
    border-top: 1px solid var(--border); margin-top: 56px; padding: 24px 0 40px;
    font-size: 0.85rem; color: var(--muted);
  }
  footer p { margin: 0 0 6px; }

@media (max-width: 460px) {
  .bar { flex-wrap: wrap; gap: 8px; }
  nav { margin-left: auto; }
  nav a { margin-left: 14px; font-size: 0.85rem; }
}